Comparison of the 1-year surgical outcomes of ab interno trabeculotomy using three types of microhooks

Purpose We compared the 1-year surgical outcomes of microhook ab interno trabeculotomy (& mu;LOT) using three types of microhooks. Methods We retrospectively analyzed 81 eyes that underwent & mu;LOT, in which three microhooks, the Sinskey hook, Tanito Micro-Hook-trabeculotomy-device (TMH), and Matsushita ed. TMH, were used. We collected the data from the medical records. We analyzed the success rates and risk factors. Failure was defined as the need for additional surgery for IOP reduction, loss of light perception, and IOP & GE;22 mmHg and IOP reduction <20% (definition 1), IOP & GE;17 mmHg and IOP reduction <20% (definition 2), IOP & GE;15 mmHg and IOP reduction <25% (definition 3), or IOP & GE;12 mmHg and IOP reduction <30% (definition 4) at two consecutive follow-up visits. Results Twenty-six eyes underwent & mu;LOT using the Sinskey microhook (group S), 21 eyes using the TMH (group T), and 34 eyes using the Matsushita ed. TMH (group M). The mean postoperative IOP and IOP-lowering medication score decreased significantly. The respective success rates among groups S, T, and M did not differ significantly (definition 1, 65.4%, 61.9%, and 55.9%; definition 2, 42.3%, 47.6%, and 32.3%; definition 3, 15.4%, 28.6%, and 23.5%; definition 4, 0%, 9.5%, and 2.9%). In group S, the hyphema-related IOP spikes decreased within 2 weeks postoperatively, and in group M, the non-hyphema-related IOP spikes decreased significantly. Conclusion The 1-year surgical outcomes and complications after & mu;LOT did not differ significantly among the three microhooks. The differences in the microhook tips might be associated with postoperative transient IOP spikes.